Don't use Slayers at first. Go to the Evox forum here and read the tuts. It's very easy to create a basic Evox boot disc. Boot to that, which will set up an FTP server. Back up your files, then use Slayers to format the new drive (and install Evox/apps), then copy your E: data back over to the new drive.
On a related note, I was disappointed after using slayers. It was fun modding my box. Getting the hardware modded is only half the battle. I haven't learned the proper way to install and configure apps because Slayers means you don't have to learn. It's a great tool if you just want the thing to work, but a definate buzzkill if you're enjoying learning how to mod. Just my opinion.